Upper Three Mile #1 is a privately owned earth dam located in Jackson, Colorado, along Three Mile Creek. Constructed in 2006 by North Park Engineering & Consulting, Inc., this recreational structure stands at 37 feet high and spans 353 feet in length. With a storage capacity of 75 acre-feet and a surface area of 5 acres, the dam serves multiple purposes, including fish and wildlife pond management and recreation.

Despite its low hazard potential, Upper Three Mile #1 has an unsatisfactory condition assessment as of 2010. The dam is regulated by the Colorado Department of Water Resources and undergoes regular inspections and enforcement to ensure public safety. With a moderate risk rating of 3, the dam poses some potential risks that are actively managed through risk assessment measures.

Water resource and climate enthusiasts can appreciate the ecological significance and engineering feat of Upper Three Mile #1, which not only provides recreational opportunities but also supports fish and wildlife habitat. As a regulated structure in a scenic location, this dam serves as a reminder of the importance of sustainable water management practices in preserving natural ecosystems and ensuring community safety in the face of changing climate conditions.